Vacuum indicator

ABSTRACT

An apparatus for withdrawing blood from a body vessel of the type including a tube with a partial vacuum pressure therein sealed at an open end by a flexible stopper, a needle having a sharp end for penetrating a vessel, an interior blood carrying cavity, an opposite sharp end, and a sleeve attachable to the needle so that the opposite end of the needle extends into the sleeve and adapted for receiving the stopper so that, when the one needle end penetrates the vessel, the stopper moves within the sleeve toward the opposite needle end which punctures the stopper and causes the blood to be drawn through the interior of the needle into the tube. In order to avoid unnecessary damage to blood vessels from attempts to withdraw blood with tubes which have lost their partial vacuum pressure, a quantity of material such as hemoglobin having a color which varies with the pressure about it is disposed within the tube before it is evacuated. The material can be dry and painted on the tube walls or liquid. Other indicators include cytochrome, myoglobin, heme and leucobases. In a further embodiment, two objects which have different air resistances, so that in full or partial pressure they fall under the influence of gravity, are disposed within the tube.

United States Patent 1191 Elllfitt 1451 Apr. 2, 1974 1 VACUUM INDICATORJohn Elliott, Philadelphia, Pa.

[73] Assignee: Angelika Elliott, London, England [22] Filed: Feb. 23,1972 [21] App]. No.: 228,687

[75] Inventor:

52 us. (:1 128/2 r, 116/114, 23/230 B,

23/254 R, 23/253 TP,'128/276 51 1111. c1 A6lm 1/00 58 Field 61 Search128/2 F, 2 R, 275, 276,

128/297, DIG. 5, 272, 214 B, 214 D, 214 E, 214 F; 73/388, 389; 141/95,7,230 B;

23/254 R, 253 TP; 215/8, D16. 3; 116/114; I 206/D1G. 12, DIG. 29, 63.2 R

[56] References Cited 7 UNITED STATES PATENTS 3,200,813 8/1965Christakis 128/2 F 3,334,628 8/1967 Saemann 128/276 3,093,242 6/1963Huyck 206/632 R 3,175,553 3/1965 Mattson... 128/2 F 2,965,255 12/1960Gcrarde... 128/276 3,322,114 5/1967 Portnoy 128/2 F OTHER PUBLlCATlONSOrthopedic Equipment Co., REDl-VAC, 2/7/64 Primary Examiner-Dalton L.Truluck Assistant ExaminerHenry J. Rccla Attorney, Agent, orFirm-Cushman,

Darby &

Cushman [57] ABSTRACT An' apparatus for withdrawing blood from a bodyvesse] of the type including a tube with a partial vacuum pressuretherein sealed at an open end by a flexible stopper, a needle having asharp end for penetrating a vessel, an interior blood carrying cavity,an opposite sharp end, and a sleeve attachable to the needle so that theopposite end of the needle extends into the sleeve and adapted forreceiving the stopper so that, when the one needle end penetrates thevessel, the stopper moves within the sleeve toward the opposite needleend which punctures the stopper and causes the blood to be drawn throughthe interior of the needle into the tube. In order to avoid unnecessarydamage to blood vessels from attempts to withdraw blood with tubes whichhave lost their partial vacuum pressure, a quantity of material such ashemoglobin having a color which varies with the pressure about it isdisposed within the tube before it is evacuated. The material can be dryand painted on the tube walls or liquid. Other indicators includecytochrome, myoglobin, heme and leucobases. [n a further embodiment, twoobjects which have different air resistances, so that in full or partialpressure they fall under the influence of gravity, are disposed withinthe tube.

4 Claims, 6 Drawing Figures PATENTEU APR 2 197 SHKU 1 Bf 2 Km NW v w :&

VACUUM INDICATOR BRIEF DESCRIPTION OF THE PRIOR ART AND SUMMARY OF THEINVENTION:

The invention relates to an apparatus for removing blood of the type inwhich a hollow needle which is insertable into a blood-carrying vesselis in communication with a tube having a partial vacuum pressure thereinso that when the needle penetrates into the blood-carrying vessel theblood is drawn through the hollow needle into the tube.

The removal and analysis of blood is one of the most common and usefulmedical techniques now in use. Blood removal can be accomplished in anyof a number of ways and a variety of devices are available on the marketfor that purpose. One of the most widely used devices includes a. tubewith a partial vacuum pressure therein which is sealed at its-open endby a flexible stopper. This tube is usually constructed of glass, comesin a variety of sizes and has a sterilized interior for receiving bloodsamples. A disposable needle having two sharp ends and a hollow interioris attachable, for example, by threads to a plastic sleeve member whichreceives the stopper in the tube so that the stopper and tube can movewithin the sleeve toward one sharp end of the needle which protrudesinto the sleeve toward the stopper. v

'When the sharp end of the needle protruding from the plastic sleeve isinserted into a body vessel a drop of blood will normally appear in'theplastic sleeve. At this time, the tube can be pushed within the sleevetoward the needle so that the sharp end of the needle penetrates therubber stopper and accordingly communicates with the interior of thetube which is at a partial vacuum with the interior of theblood-carrying vessel. Because of the pressure differential, the bloodin'this vessel is drawn through the hollow disposa'ble needle tains apartial vacuum pressure. The tubes are, of

course, normally evacuated at the manufacturers facilities prior toshipment to the location where blood is withdrawn. That shipment mayinvolve considerable rough handling. Further, there is frequently adelay of a considerable amount of time which may be months or even yearsbetween when the tubes are evacuated and when they are used forwithdrawing blood. The result is that frequently the partial pressurewithin the tube has been lost at the time in which the device is used.

If there is no pressure within the tube when the needle is inserted intothe'blood vessel, of course, blood is not drawn back into the vacuumtube. The user of the device has no way of knowing whether the failureto draw blood is because of the absence of a partial vac-, uum pressurein the tube or because he has failed to insert the needle in the vessel.Normally, the individual using the device will make several attempts toinsert the needle into the vessel before assuming that there is nopressure within the tube; the result is unnecessary and frequentlyextensive damage to the blood carrying vessel. Since, in connection withmany medical treatments, blood must be withdrawn many times daily, evenan occasional use of a tube without vacuurnpressure is painful anddamaging to the patient.

The present invention .relates to an apparatus whereby an indicator isplaced in the tube before evacnation. This indicator has acharacteristic, which varies as a function of the partial pressuretherein so that the loss of that partial pressure can easily be seen bythe technician before he attempts to remove the blood sample. One of theindicators which is believed to be particularly advantageous ishemoglobin which is a substance normally produced by the body and whichis responsible for the difference in color between arterial and veinousblood. The indicating material can be painted as a dry laquer on thesides of the vessel or alternately a small quantity of a liquidmaterial, such as hemoglobin can be simply disposed in the indicatingtube. Other materials, believed suitable as indicators and which willchange color when the vacuum pressure is lost, include different typesof cytochrome, myoglobin, heme and various leucobases. It is, of course,important that any indicator in the vacuum tube not interfere with anyparticular test which is to be carried out and an appropriate indicatoris'preferably chosen at least partly on that basis. The claims of thispatent are directed particularly toward an indicator whose rate of fallin the tube indicates the pressure. In one embodiment this body is anobject having a blade causing spinning at the object as it falls in air.In another embodiment a ball and feather are provided so their rates offall can be compared.

Such anindicator can, of course, be used to indicate absence or presenceof a partial vacuum in any device and while the present invention findsparticular utility in connection with the apparatus described above,there is no intention to limit the invention to this particular devicefor withdrawing blood.

BRIEF DESCRIPTION OF THE DRAWINGS:

FIG. 1 shows an exploded view of a device for draw-' ing blood from abody vessel including a tube having a partial vacuum pressure thereinand an indicator painted on a portion of the interior tube walls forindicating a loss of that partial vacuum pressure.

FIG. 2 shows a tube which can be used in connection with the bloodwithdrawing device of FIG. 1 whereby a liquid indicator is disposedwithin the tube for indicating the absence or presence of a'partialvacuum pressure. r I

FIG. 3 illustrates the device of FIG. 1, assembled and in use with thesharp end of the needle, which pro trudes into the sleeve, puncturingthe rubber stopper and communicating with the interior of the tube forwithdrawing blood from the body vessel.

FIG. 4 illustrates another embodiment with two objects having differentair resistances so that at full or partial pressure they fall atdifferent rates under gravity. 1

FIG. 5 illustrates another embodiment with a vaned object which spinswhen falling in .full or partial pressure.

ject of FIG. 5.

DETAILED DESCRIPTION OF THE DRAWINGS:

Reference is now made to FIG. I, which shows an exploded view of anapparatus for withdrawing blood as discussed briefly above. Thisapparatus includes a disposable needle 20 which has sharp ends 22 and 24and a hollow interior passage 26 connecting ends 22 and FIG. 6illustrates a perspective view of the vaned ob- I 24. Disposable needleis attachable to a sleeve member 28 which is preferably plastic withthreads 30 of needle 20 mating with threads 32 of sleeve 28 so that end24 protrudes into the interior of the sleeve 28 as illustrated in FIG.3. Sleeve 28 is preferably reusable.

Tube 34 is preferably constructed of glass and after sterilization isevacuated to a partial vacuum pressure sufficient to withdraw asatisfactory quantity of blood in the fashion described above. Afterevacuation, tube 34 is sealed by the flexible stopper 36 which may be ofrubber or other suitable material. Sleeve 28 and stopper 36 mate so thatstopper 36 of the tube 34 are moveable within sleeve 28 in asubstantially airtight connection toward and away from the protrudingend 24 of disposable needle 20.

As illustrated in FIG. 3, when needle 20, sleeve 28, and tube 34 areassembled and the end 22 of the needle 20 inserted into the body bloodvessel, stopper 36 and tube 34 can be moved toward end 24 of needle 20so that end 24 punctures the flexible member and communicates theinterior of tube 34 which has been evacuated to a partial vacuumpressure with the interior of the blood vessel. Normally, suchpuncturing would be accomplished after a drop of blood has appearedwithin the interior of sleeve 28 indicating that the vessel had beencorrectly penetrated. The difference in pressure between the interior oftube 34 and the vessel penetrated by needle 20 causes blood to be drawninto the tube 34. When a satisfactory amount of blood is disposed intotube 34, end 22 of needle 20 is withdrawn from the blood vessel. Needle20 is then detached from sleeve 28 and discarded, while sleeve 28 isreused. Stopper 36 and tube 34 can then be withdrawn from sleeve 28 withthe opening created by the needle 26 being sealed so that the blood iskept sealed within tube 34 until just previous to analysis by thelaboratory, thus minimizing the danger of contamination. After analysistube 34 and stopper 36 can then be discarded.

As discussed above, it is of considerable assistance to the people usingthe device and of considerable advantage to the individual whose bloodis being withdrawn if the presence or absence of a partial vacuumpressure within tube 34 can be easily ascertained previous to an attemptto withdraw blood. In the embodiment illustrated in FIG. 1,a quantity ofmaterial 40, which in this embodiment is painted dry on a portion of theinterior walls comprising tube 34, serves as that indicator, changingcolor when the vacuum pressure is lost in tube 34. As discussed abovethis can easily happen during the considerable time interval and roughhandling which takes place between the evacuation and use. One suchmaterial which is believed to be particularly advantageous is hemoglobinwhich is the blood substance responsible for the difference in colorbetween veinous and arterial blood. In a partial vacuum pressure, thehemoglobin will appear as a dark red.

However, should the vacuum pressure be lost and the quantity of oxygenwithin tube 34 rise, some of that oxygen will react with the hemoglobincausing the color to change to a bright red. Since, normally, the lossof pressure will not occur immediately before use of the device, it isnot important that the indicator 40 be quick acting.

There are a number of other possible substances which can satisfactorilyserve as indicators. These substances include different types ofcytochrome, myoglobin, heme and various leucobases. It is important, ofcourse, that any particular indicator being used not interfere with theparticular analysis which is being carried out, and the indicator ispreferably chosen at least partially for that reason.

As an alternative to painting the dry indicator on the side of the tube34 before it is evacuated, a quantity of liquid indicator 50 can bedisposed in tube 34 as illustrated in FIG. 2, provided of course thatthe indicator remains liquid at the chosen partial vacuum pressure. Anyother way of disposing a suitable indicator into tube 34 so that thechange in color can be easily and quickly observed from the exterior oftransparent glass tube 34 can, of course, be employed.

Reference is now made to FIGS. 4-6, which illustrate further embodimentsof the invention in which the presence or absence of a vacuum can bevisually determined by observing the free fall by gravity of one or moreobjects within the tube. In FIG. 4, a first object 50, such as a smallplastic ball, and a second object 52 such as a bird feather orfeatherlike object are disposed within'tube 54 which is sealed bystopper 56. It is well known that in a vacuum all objects fall under theinfluence of gravity at the same rate. However, in a full or substantialpressure the air resistance of an object also bears on its fall rates.Thus, in air, feathers fall at a slower rate than spherical balls. Thisphenomenon can be used to simply detennine a leakage into tube 54 bysimply inverting the tube and observing the fall of objects 50 and 52.If there is a substantial pressure within tube 54, then object 52because of its greater surface area will fall at a markedly lower ratethan object 50. Objects 50 and 52 can be constructed of any suitablematerial which will not break tube 54 and which will not affect anysubstance drawn into tube 54. A soft plastic is believed satisfactory.

In the embodiment of FIGS. 5 and 6, a single object 60 having a pair ofvanes 62 and 64 is disposed within tube 66 which is sealed by stopper68. Vanes 62 and 64 are disposed at a slight angle to the horizontalwith most of the mass of object 60 below the vanes so that when object60 falls through the air it spins like helicopter' blades. In a vacuum,of course, no spinning tube 66 in its fall.

While the embodiments of the invention described above are related to adevice for withdrawing blood, this invention can, of course, be used forindicating the presence or absence of a partial vacuum pressure in anycontainer in which the changing color can be ob served from the exteriorthereof. Any other changes and modifications in the above embodiments ofthe invention can, of course, be made without parting from the scope ofthe invention, and that scope is intended to be limited only by thescope of the appended claims.

What is claimed is:

1. An apparatus for removing blood having a tube with at least partialvacuum pressure therein below atmospheric pressure and a needleconnected to said tube with an end adapted for penetrating into a bloodcarrying body vessel and an interior blood transferring cavity so that,when said end has penetrated into a vessel, said cavity is in pneumaticconnection with the interior of said tube and blood from that vessel isdrawn through said cavity into the interior of said tube, theimprovement comprising means within said tube for indicating by a changein visual characteristic the loss of said partial vacuum pressureincluding an object within said tube having a body portion and a bladeportion extending from said body portion and curved so that in free fallin air said object is rotated but in free fall in vacuum does notrotate.

2. An apparatus as in claim 1, wherein said apparatus further includesflexible means sealing an open end of said tube and a sleeve member withsaid needle attached to one end and receiving said flexible means at theother end and wherein said needle has an end, opposite said end adaptedfor penetrating said vessel, for puncturing said flexible means when aforce is exerted on said tube to cause said penetrating end of saidneedle to penetrate said vessel and said puncturing end to puncture saidflexible means as said sealing means moves toward said needle withinsaid sleeve member.

3. An apparatus as in claim 1, wherein said tube is transparent.

4. An apparatus for removing blood having a tube with at least partialvacuum pressure therein below atmospheric pressure and a needleconnected to said tube with an end adapted for penetrating into a bloodcarrying body vessel and an interior blood transferring cavity so that,when said end has penetrated into a vessel, said cavity is in pneumaticconnection with the interior of said tube and blood from that vessel isdrawn through said cavity into the interior of said tube, theimprovement comprising means within said tube for indicating by a changein visual characteristic the loss of said partial vacuum pressureincluding a roughly spherical ball and feather'like object roughly thesame size as said ball but presenting a greater surface area in freefall within said tube.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent NO.3,800,780 Dated Apri 2 1974 Inventor(s) John lllott It is certified thaterror appears in the above-identified patent and that said LettersPatent are hereby corrected as shown below:

Column 1, line 53, change "no pressure" to -atmospheric pressure.

Column 1, line 61-62: change "no pressure" to -atmospheric pressureSigned and sealed this 17th day of September 1974.

(SEAL) Attest:

MCCOY M. GIBSON JR. C. MARSHALL DANN Attesting Officer Commissioner ofPatents

1. An apparatus for removing blood having a tube with at least partialvacuum pressure therein below atmospheric pressure and a needleconnected to said tube with an end adapted for penetrating into a bloodcarrying body vessel and an interior blood transferring cavity so that,when said end has penetrated into a vessel, said cavity is in pneumaticconnection with the interior of said tube and blood from that vessel isdrawn through said cavity into the interior of said tube, theimprovement comprising means within said tube for indicating by a changein visual characteristic the loss of said partial vacuum pressureincluding an object within said tube having a body portion and a bladeportion extending from said body porTion and curved so that in free fallin air said object is rotated but in free fall in vacuum does notrotate.
 2. An apparatus as in claim 1, wherein said apparatus furtherincludes flexible means sealing an open end of said tube and a sleevemember with said needle attached to one end and receiving said flexiblemeans at the other end and wherein said needle has an end, opposite saidend adapted for penetrating said vessel, for puncturing said flexiblemeans when a force is exerted on said tube to cause said penetrating endof said needle to penetrate said vessel and said puncturing end topuncture said flexible means as said sealing means moves toward saidneedle within said sleeve member.
 3. An apparatus as in claim 1, whereinsaid tube is transparent.
 4. An apparatus for removing blood having atube with at least partial vacuum pressure therein below atmosphericpressure and a needle connected to said tube with an end adapted forpenetrating into a blood carrying body vessel and an interior bloodtransferring cavity so that, when said end has penetrated into a vessel,said cavity is in pneumatic connection with the interior of said tubeand blood from that vessel is drawn through said cavity into theinterior of said tube, the improvement comprising means within said tubefor indicating by a change in visual characteristic the loss of saidpartial vacuum pressure including a roughly spherical ball andfeather-like object roughly the same size as said ball but presenting agreater surface area in free fall within said tube.